This invention relates to a filtration system for a swimming pool, and more particularly to a filtration backwashing system for a swimming pool.
Filtration systems for swimming pools including circulating means for backwashing the filtration system are well known in the art, as illustrated in the following U.S. Pat. Nos.:
3,061,100 Fehlmann--Oct. 30, 1962 PA1 3,220,553 Growall et al--Nov. 30, 1965 PA1 3,420,376 Smith--Jan. 7, 1969 PA1 3,581,895 Howard--June 1, 1971 PA1 3,801,992 Sable--Apr. 9, 1974
Fehlmann and Growall et al employ a single reversible pump and motor for reversing the circulation of swimming pool water through a filter media.
Richards U.S. Pat. No. 25,865, issued Sept. 21, 1965, discloses a backwashing system for backwashing filter beds and also for removing trash from a strainer basket, when the circulation of liquid is reversed.